平面、圆柱面和球面的气体渗碳数学模型

Models for Gas Carburizing of Plan, Cylinder and Ball

建立了包括平面、圆柱面和球面在内的统一的气体渗碳数学模型 :Cτ=D(2 Cx2 +shape(x -R0 )Cx) ,并将碳的扩散系数作为温度和含碳量的函数表示为D =D0 .4 exp(-Q/RT -BC(0 .4 -C) ) ;将碳的传递系数作为温度的函数表示为 β =β0 exp(-E/RT) ;内边界条件为含碳量是固定值 ;碳势和温度视为时间的线性函数。结合按此模型的模拟计算 ,讨论了表面形状、扩散系数和传递系数中有关参数对碳浓度分布的影响规律。

The models established in this paper for gas carburizing of plan,cylinder and ball are given byCτ=D( 2Cx 2+shape(x-R 0)Cx),in which carbon diffusivity (D) is defined as function of temperature (T) and carbon consistence (C),i.e.D=D 0.4exp(-Q/RT-B C(0.4-C)),carbon transfer coefficient is expressed as a function of temperature,β=β 0exp(-E/RT)and carbon potential and temperature as linear functions of time.The influences of carbon diffusivity and carbon transfer coefficient on carbon distribution are discussed according to the results of simulating.